Ship&#39;s instrument



Aug. 16,1927. l 1,638,970y i G. WALKER v sHIP's INSTRUMENT Filed Aug. 23, 1919- 7 sheets-sheet 1 DX f3 l /y' n ja .52 Hf f6 6/ 0 a1 551 x62 I 1L f iwi" 57 cf." l l `1 j j y LLL 77 Aug. 16, 1927. 1,638,970

G. WALKER SHIP S INSTRUMENT Fild Aug. 23, 1919 '7 Sheets-Sheet 2 1,638,970 Aug 16 1927. G. WALKER SHIPS INSTRUMENT Filed Aug. 25. 1919 '7 Sheets-Sheet 5 fave z- 7 de ye Mad/fe?" y Aug. 1e, 1927. 1,638,970

G. WALKER SHIP S INSTRUMENT Filed Aug. 25, 1919 '7 Sheets-Sheet 4 Aug. 16, 1927. 1,638,970

G. WALKER SHIP S INSTRUMENT Filed Aug, 25, 1919 7 sheets-sheet 5 Gerry/ye 3064276674 (tl/a S Aug. 16,1927. A 1,638,970

G. WALKER SHIP S INSTRUMENT Filed Aug. 23, 1919 v sheets-sheet 6 \\\\v\\\\\\\\\\\\\\\\\Y feazye 06242/6624 Aug. 16,1927.

G. WALKER SHIP S INSTRUMENT Filed Aug. 25, 1919 '7 Sheets-Sheet 7 'Y '/-z-Uezz-o 2.'

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lfatented Aug. ,16, 1227.(

, -.UNI-RED4 *STATES PATENT- oFFlc-E. i

GEORGE wALxER, or NEWTON, iinevssacrxtrsii'rfgs.

i Sams" INsrnUMENT.

', application med august as, 1919.'. s 'erm No. 319,392.

This invention relates to a ships instrument for counting during predeterminedy 'periods of time,

number of revolutions of each propeller and such as'reach minute, the

the average number of revolutions lofy all the propellers, p uring and indicating the distance travelled and for automatically meas- .by the ship whether at constant or varying speeds.

Patent of the 273,744Lled January 29, 1919, an instrument is shown which. indicates on suitable former `application for Letters In my United States .Serial Np dials, for predetermined .intervals of time y(as each minute), the eXadt number of revolutions of each "propeller and the averageV number of revolutions of all the propellers.

My 'said former instrument also indicates l the number of miles the ship has travelled,

determined by the number ofl propeller revo- --lutions (average) required to drive the ship a mile at ygiven propeller speeds. To accomplish thishowever a' governor arm or hand must bel manually adjusted for every different propellery speed to correspond lto the I numberofpropeller revolutions required to drive thelshi'p .a mile at that speed. So long as the given propeller speed at'which the governor arm is set is accurately maintained the instrumentl will jcorrectly register the distance travelled; but if the given propeller speed is not maintained the distance indicator will not correctly register the distancev travelled. For example, if-a particular ship ,is driven 10 knots'per hour, at a propeller speed of 148 revolutions per minute the. propeller revolutions will be 888 per knot.

X ormer yinstrument the governor hand would be set vat 888 andthe distance travelled would then be accurately registered so lpng as the speed of 148 revolutidns per minute is maintained. As a practical matter however it is'vdifiicult if not impossible to maintainl a propeller speed Jo f exactly. fthe number of revolutions per minute .ordered and in the example assumed ifthe propeller `speed varied from'148 R. P. M .by even a very slight amount the distance travelled would vary and-the instrument set for exactly 148` R. would recordthe distance incorrectly.

vantage to be obliged manually to set the governor hand Ain accordance with the number Q revolutions per mile at every change of speed.

In my present instrument, insteadl of controlling the distance indicator bythe,l number of propeller revolutions per mile, the distance indicator is controlled by the number of propeller lrevolutions per minute, that is,

by the propeller speed. This instrument will y,

automatically and accurately register the actual 'distance the ship has travelled, whether at constant or varyin speeds,"and without manual yadjustment o any kind toadapt the instrument tovdilerent propeller speeds.

In the accompanying drawings which illustrate theinventionf- Figure 1 is a diagrammatic vieu7 showing 75 the electrical connections;

Figure 2 is a sectional view Ona plane through line 2-2 of Fig. 3 looking in the direction of. the arrows,. and showing the mechanism of the instrument in side eleva\ tionpc'ertain parts beingomitted for the sake of clearness; A

Figure 3' is a sectional view of the instrument on a plane through line-B of Fig. 2;

-FigureA is a sectional view on through line 4-4 of Fig. 2; Y 4,

Figuret is a sectional view ontan enlargedl scale showing nism at the rightl of Fig. 2 on a plane through line 5-5 of Fig. 2; L

*Figure 6 is aplan view 'of the instrument with the cover partly broken away;

' Figure 7 `is an enlarged view in detail corresponding to the right hand 'part of Fig. 2;

Figure 8 is an enlarged detail in elevation showing parts of the distance indicator mechanism;

-' Figure 9. is a. plan view of the upper averya plane revolution o starboard and port propeller shafts of a vessel having two propellers.' rllhe propeller shafts carry respectively insulating rings 1 and l', havin contact pieces 2 and 2. Each starboard propeller shafts S will connect contacts a b through contact piece 2 thereby energizing electro-magnet 3 through the circuit including a, b, and switch 72, connecting the main lead lines A and B, which are supplied with current from any suitable source of electrical energy.

Similarly each revolution of port propeller shaft P will energize electro-magnet 3 through the circuits including conductor c, contacts c', 2, cZ, and conductor d, connecting lines A and lj.

yFlach time electro-magnet 3 is energized I it operates arm 4 (Figs. 2, 3 and 7) which lll) is connected to the armature vof the magnet and is pivoted on a stud 5 fixed to the base plate of the casing or frame. The 'arm 4 is held on the stud by a collar 6 (Fig.y 7) fastened to the stud. A spring tends to pull the arm'4 away Afrom the magnet,y and a stud 7 mounted on the base plate acts as a stop to limit the movement of the arm in that direction. At the free end of the arm 4 is" an oscillating pawl 8 pivoted on stud 9.

The pawl 8 engages and actuates a ratchet wheel 10 fastened solidly to a rotatable shaft 11. Shaft l1 (Figs. 2, 3, 4, 5 and 7) turns at its lower end on the base plate of the casing, and at its upper end in plate X, through which the shaft extends. Fixed to the same shaft 11 with ratchet wheel 10 and turning therewith is a gear` wheel 12 (Fig.'5). 18` (Figs. 5 and 7) is an oscillating arm pivoted on shaft 11l and normally urged to the left, that is, toward gear 17. by a. spring 14 fastened to plate X. (tear wheel 15, a duplicate of gear wheel 12, is journalled on arm 18 by a. stud 16, and is rpermanently in mesh with gear wheel 12.

Gear wheel 17, identical with gear wheels 12A and 15. is fixed to a revolving shaft 18, which turns at one end in plate X and at the other end in a supporting bracket 19 l fastened to plate X. A heart shaped cam 20, formingvpart of the resetting mechanism is fixed to gear wheel 17, and a hand or pointer 21 (Fig. 6) is fixed to the end of shaft 18.

From the foregoing it will be seen that each time electro-magnet 3v is energized by one revolution of the propeller shaft S, with gears 15 and 17 in engagement-,t ratchet wheel 10 will be revolved lthe distance of one tooth, and wheel 10, acting through shaft 11, gear wheel 12, gear wheel 15, gear wheel 17 and shaft 18 with turn hand 21 on dial D1. v A

Similarly hand 2.1A on dialD2 willbe operated through gear wheels 15A and 17'. and shaft 18A, when gears 15A and 17A are in Maggio mesli. rlihe parts 13A, 14A, 15A, 16A, 17A, 18A, 19A and 2()A are identical with the corresponding parts numbered 13 to 20 through which the hand 21 is operated.

ltf the pair of gears 15 and 17, and the pair of gears .15A and 17A, are alternately engaged and disengaged at predetermined intervals of time, say each minute. the number of revolutions of the starboard propeller shaft for the successive predetermined pe'- riods of time will be alternately indicated on dials D1 and D2, which will show minute by minute (or other predetermined period) the propeller sp-eed, the revolutio-n counter mechanism for each dial ceasingvto operate the instant the other begins to operate.

Bv precisely ksimilar mechanism the port propeller shaft F actuates the hands 2l and 21A on the pair of revolution counter dials D3 and Di* for the port propeller, through electromagnet 3", ratchet wheel 10', shaft 11', and mechanism (not shown) identical with that in Fig. 5. r1`he parts 4, 5', 6', 7, 8', 9', 10', 11', 18, and 18A are like the corresponding parts 4, 5 etc. already described. rlhus the speed ofl the portpropeller will be indicated minute by minute (or other predetermined period) on the dials D3 and D4 alternately.

To'obtain the average speed of the two propellers, revolution (counter mechanism (not shoWn)-identical with that shown in Fig. 5 is provided between the pair of revolution counters for the starboard propeller and the pair for the port propeller. The average revolution counter mechanism actuates alt-ernatelv theA hand 21 on the upper dial D5 and the hand 21A.on the lower dial D6. rFhe central shaft 51 (Figs. 2, 4 and 7) corresponds to shaft 11 and acting through mechanism like that shown in Fig. 5 alternately' drives the average speed indicator hands 21 and 21A. in the same manner as already described.

' Shaft 51 is rotated at the average speed of the shafts 11 and 11 by the following meansz-G-ear wheels 46 and 46 (Figs. 2. 4 and 7) fast on shafts 11 and 11Lrespec- 4tively mesh with gear wheels 46A and 46A.

Gear wheel 46A meshes with gear wheel 47 loose on shaft 51, and gear wheel 46A meshes with ear wheel 47 loose on shaft 51. Bevel gears 48 and 48 are fixed respectively to gears 47 and 47. etween the bevel gears 48 and 48 and meshing therewith is a bevel pinion 49 carried bv arm 50 which is fast on shaft 51. The differential gearing thus provided Lwill cause the shaft 51 to rotate at the average speed of the shafts 11 and 11. The index hands 21 and 21A will therefore indicate'the average revolutions of the starboard and port propellers.

lll)

By way of illustration and not of limital whereby the instrument is adapted for use on any ship having al propeller speed'- not exceeding 480 revolutions per y minute. Under the asumed conditions the ratchet wheels and 10 will also have 480 teeth, and the ratchet wheels 10 and 10 and consequently the hands 21 or 21A, and 21 or 21A', will be turned 1/480 of a revolution at each complete revolution of the propeller'. It is to be understood' however that the number of\ \ratchet teeth and of the scale indications on the dials might be greater or smallernvithout departing from the principle of the invention, thereby adapting the instrument for use on ships having a dif-` ferent maximum propeller speed from that assumed for the purpose of illustration.

I will now describe the mechanism by.

which the two revolution counter mechanisms of al pair are alternately engaged and disengaged, and reset to zero or initial position ready to start again. N Referring to Fig. 5," gear 12, which is atall times in operative condition, will be turned in a clockwise direction by electromagnet 3. GrearsA and 15A, carried by arms 13 and 13A, are always in mesh with gear 12. Springs 14 and 14A acting on arms 13 and 13A, respectively, tend to 'urge -gears 15 and 15A into engagement with gear`sv17 and 17A respectively. Ratchet wheel 27 mounted on plate X is provided with a seriesl of spaced lugs 28 which act on thevvv end o arm 13 and alternately'lift gear wheel 15 out of mesh with gear wheel 17, and` allow it to engage gear wheel 17 as the ratchet 27 is revolved in a counter-clockwise direction. The ratchet wheel 27 is turned by a pawl 29, pivoted by a pin 30 on bar 31. Bar 31 extends across the instrument and has a similar pawl 29 for each of the revolution counter mechanisms, acting on a similar ratchet 27 in each set for controlling the hands of the upper dials, namely' dials D1, D3 and D5, of each pair. lVhen the end of 'arm 13 rests on one of the lugs 28 .gears 15 and 17 will be disengaged and therefore the hand 21 will be inoperative; but when the end of arm 13 drops off from ithe lugs 28 the gears `15-Oand 17 will engage, and the gear 17 and hand 21y will be turned from gear 12. v

The revolution counter is reset to its zero. or initial position after being disconnected from gear 15 through heart cam 2() which is fast ongear wheel 17. Arm 23 by pressing upon heart cam 20 inany positionof the latter will automatically turn it, to-

gether with the gear wheel 17 and hand 21, to the position shownwhich is zero or starting position. The action of the heart cam is in accordance with the well known principle of a stop watch. The arm 23 is pivoted to the plate X at 22 and is pressed toward the heart cam by a spring 25. A

projection or tooth 23 on the side of arm 23 is engaged and disengaged by the lugs 28 on ratchet wheel 27, alternately to lift the 27 with relation to the teeth to act as herein after described, andthe bar 31 has an endwise movement to the right sutficient'for the pawl 29 to turn the ratchet wheel 27 the distance of one tooth. v

. Assuming 'the parts to be in the position 4 shown in Fig. 5 and the instrument to be in operation, the hand '21. will be in zero position and the gear wheel 12v will be -revolving step bystep in a clockwise direction but out of engagement with gear wheel 17. l

If now bar 3l is shifted once to the right, ratchet wheel 27 -will be turned the distance of one tooth and-the following actions will take place simultaneously z--Armv 13 will drop 'o if from a lug 28 thus throwing gear wheel 15 into mesh with gearwheel 17; gear wheel 17 and consequently hand 21 `will start to `turn in aclockwise direction; arm 23. will be'lifted out of contact with heart cam 20 by one of the lugs 28; and brake' arm 24 slides along the face of a lug 28 and is `stillheld out of contact with gear wheel 17 If now bar 31 is again shifted to thel right the following actions will simultaneously occur:-A lug 28 will engage the end of arm 13 and lift gear wheel 15 out of con` tact with gear wheel 17; arm 23 will ride along the face of a lug 28 and lremain in elevated position out of contact with heart cam 20; and brake arm 24 will drop o from a lug 28 and press against gear wheel 17 holding it'against movement. This will stop hand 21 of dial .D1 and lock i-t in the position in which it was stopped. l

If now a third movement to the right .is

given to bar 31 the following actions will simultaneously take place :-'Arm 13 will ride'along the face of a lug 28 holding gear wheel 15 out of engagementwith gear wheel 17; arm' 24 will be lifted by a lug 28 to 'release gear wheel 17'; and arm 23 will drop off from a lug 28 and strike heart cam 20, returning gear wheel 17 and with it hand 21, to their zero or initial position, and locking them in 'that position. c Y.

.Inasmuch as bar 31 carries an actuating pawl 29 associated with all the upper revolution counter mechanisms which control the hands 21, 21', and 21f of ldials D1, D, and D5, it wil-l be seen that all ofl these parts will the movements of bar 31.

tml

lln like manner Ithe lower set of revolution counter mechanisms of the several pairs, to

31A, are the same in construction and operation astlie corresponding parts-22, 23, etc. already described.

The bar. 31 is operated to start, stop and reset the revolution counter mechanisms at predetermined intervals by automatic means., under the Coutrol'ot a chronometer 38 (Fig. 1). Arm 33 (Figs. 2 and 7) Which shifts bar 31, carries the armature of electro-mag net 37 by which Yit is actuated. Electromagnet 37 is energized at the desired intervals of time bythe closing of circuits controlledby the chronometer. i

The chronometei` ha-nd 39 Will make one complete revolution in tvvo minutes, or onelialf a revolution in one minute. rThus it will move from contact point' 40 to Contact point 4 1, or from point 41 to 40, in one minute. llt Will be understood/that the period of one minute is ufsed merely for illustration and because it is used to reckon propeller speed by the number of revolutions per minute,but the c hronometer might he 'designed to measure any other predetermined period ottimeY desired. v Assuming that the index hands of the revolutionindicators D1, D3, D5 are at'zero position, it the chronometer hand 39 makes contact with point 40, magnet 37 Will be energized through the circuit comprising e and 41', which also is connected through line f with magnet 37, and'vvill again energize the magnet thereby stopping the upper set oit revolution counter mechanisms, leaving the indicator hands 21, 21L and 21 registering the actual number o-'revolutions of each propeller-and the `average revolutions of both propellers, during the minute just elapsed; At any time during the next minutie the upper revolution counters maybe vreset to their initial positionready to start again, but I prefer to .leave the indicator hands at rest, until just before the expiration of the next minute so that the dials Will show during approximately the Whole of each minute the propeller' revolutions for the next preceding minute, thus affording ample time for observing the readings. When the .i chronometer hand'39`reaches contact'point 42, Which'may be, say, at the expiration of 59 seconds, electromagnet 37 will again be energized, (42 being also connected to line e) and bar 31 will again be shifted thereby resetting the revolution counter to zero or initial position. Almost immediately chronometer hand 39 Will again touch contact point 40 at the end of the second minute,

thus completing the cycle and again starting the revolution counters of the upper set.

1n like manner the lovver set of revolution Y counters associated with dials, D2, D4 and D6, are operated alternately with the revolution counters of the upper set.. Starting with the index hands 21A, 21N, and 21A at zero, When chronometer hand 39 touches contact point 41 (at the same instant it stops the upper set of revolution, counters)I electromagnet 37A is energized through the circuit includ- .ing i5, and thereby swinging arm 33A (F ig.

just betere the expiration of the next minute the hand 39 will touch contact point 45 thus closing the circuit 7c, 7L and through electromagnet 3"(A and resetting the lovver set of revolution counters. At the end of the `ninute the hand 39 reaches Contact point 41 completing the cycle and again starting' the revolution vcounters of the lovver set simultaneously with the stopping of the upper set.

The bars 31 and 31A may be manually operated by push pins 32 and 32A mounted to slide in the Wall of the casing (Figs. 2, 5, 6 and 9).

Dstan ce indicator. t

As already statedthe revolution indicator dials oit the instrument herein described and illustrated in the. drawings have 480 scale graduations. The instrument is thus appropriate tor any ship having a maximum of 480 propeller revolutions, or less, per minute (or other predetermined period of time). rlhe dials may shovv any number of graduations desired provided the ratchet Wheels and gears are proportioned to correspond, but a scale of 480 graduations is sel lected as a convenient example because suit- `able/for a' class of modern destroyers of the United States Navy having a maximum propeller speed of about 470 revolutions per minute. f

rThe problem and its solution, of providing a distance indicator controlled by the propeller speed to show the actual distance in nautical miles a ship hastravelled, can best be explained by a concrete example. The

- Revolu- Revolu- Miles Speed tions per (nautical) os jfe knots minute per minute knot 74 .0S33 8` 8835 6 88. .10 8. 8O 7 '103 1166. 8.8283 s 11a .1333 8. 85

'9 133 15 8. 8667 10 148 1666 8. 88 11 162 1833 8.8365 12 v 175 .2o a 75 13 188 .-2166 a. 677 14- .201 2333 8. 6144 15' 214 .25 8. 56 16 228 2666 8. 55 17 244 .288 8.6119 18` 261 ..30 8.70 19 277. 3166 '8. 7475 20. 294 .3333 8.82 21 '315 .35 9.

If it is desired to run the shi-p at the rate for example of lO knots per hour the order is `given to drive "the propellers at a speed` of v14:8 revolutions per minute.

This will drive the shipll 2/3U nautical lmiles per ninute.. Or if the propellers turn- 74 revo'-k lutions per minute the tship will travel at the rate of 5 knots per`hour,'and will travel .08 l/3 of a knot during the minute.

Referring now `to Figs. 9 and 10 which show the average revolution .counter-dials,

electrical contact points 53 are arranged on the ldial in the path of the hands 21 and 21%, spaced on the dial ivith relation to the v scale graduations in accordance. with the foregoing table. Thus, since 74 propeller revolutions per minute willdrive the ship .08 l/3 0 amile (this being at the rate of.

5 knots per hour) a contact'point 53 is placed at graduation #74 on the dial. Similarly contact point-S53 are located about the dial to register each :0l of a knot travelled, and .each .01 (is again subdivided into. thirds, so4` that the instrument willy measure i and register. the distance the ship has. trav` elledwithin 1-/3 of 1/160 ofA a knot.

is 'desired to measure the distance' toI a smaller fraction the subdivisions `may be` smaller byplacing contact points 53 closer together, but forpractical purposes,` and by` way of illustratidn, it is vsuiicient to measure the distance travelled within 1'/3 of 171001A of ai nautical mile, which is only about 2O eet. The contact points`53 of .dial D5 areconnected by electrical conductor 52 (Fig.

f1) preferably located on the under side of the'dial, and contact points 53tor` dial De are-connected ,by electrical yconductor 52A (Figs. l and 7 cConductor 5 2 is connected withmin line. A thro'ughelectrofmagnet 63, by `lines Z and m;'and conductor 52A 4is connected with main line A through electromagnet-63 by lines' 0 and m. 'As the lhands 21 l and 21A move around fthe face of the dials they successivelyI engage contact p oints 53and energize electro-magnet 63 by which If itr or right hand numeral wheel of the counter 1' 1/30 of a. revolution each time electromag net 63 is operated. Each of the numeral 75 wheels of `the distance counter 69 carries `on its periphery ten numerals, 0 to 9 as usual,

so that each time the iirst .orright hand numeral wheel is advanced it will register 1/3 of 1/100 of a knot.4 Any desired num- 80 ber of numeral wheels may be used, six` being shown in the'drawings, the four at the left indicating knots or nautical miles, and the two at the right indicating hundredths of knots. Thus the counter shown is adapt- 85 ed to register distance up to 9999.99.2/3" 'knots To 'show' the distance 'to k1/3 kof 1/'100 lof a knot' the space between centers on the periphery of. the numeral wheel the eirtreme right (the hundredth wheel) 90 I may be divided by lines into thirds, to be observed vin conjunction with a central line marked onthe casing (Fig..6). i h

A detail of the mechanism for operating the distance'indic'ator is illustrated in Fig. 8. 95

counter 69, one third ofthe distance between centers of i-tsnumerals. Ratchet wheel 68 is loperatedby-pawl 67 carried'on the end .of arm 64. Arml 6 4is pivoted at 66 and car--l ries the armature ofnelectro-magnet 63. 10;) Each time electro-magnet 63 is energized it will turn vthe ratchet 68 oneftooth. Suppose now vthat the propellers are turning 88 (average). revolutions per minute.

ingthe minute, or at the rate of 6 knots per hour. The hand 2l in moving from with all the points 53 up to and includingy that located-atg'raduation88, each time ad- I'115 vancing the distance indicator 69 one step so 'as to lregister 1/3 pf 1/100 of a knot.v

on the distance indicator through the hand. 39'

tate the right hand number wheel of the IQQ' The ship will then travel .10` of-a knot'dur'- l10 zero to graduation 88, contacts successively.-

Therefore the distance indicator will read y revolution counter mechanism associated with dial D5 and during the next. minute from the revolution counter mechanism associated with dial D, and so on alternately and continuously; because 'the actual average revolutions of the propellers during each succeeding minute are counted by the revolution counters and by them translated into distance on the distance indi-cater.

From the foregoing it will be clear that the instrument willv record automatically and correctly the distance travelled at varying speeds. lit', for example, the ship-is building up its speed 'from 5 knots per hour, at the rate ot one knot each minute the distance indicator will show .08 1/3 -knots at.

the end of the first minute (see the above table and Fig. 9), .18 1/3 knots (i; e. .O6 1/34-.10) at the end of the second minute, .30 knots (i. e. .O8 l/-I-.lO-i-.ll 2/3) at the end of the third minute, and so on.

The mechanism for automatically placing the distance indicator alternately under the control of the two revolution counters of the pair of. average revolution counters (assos ciated with dials D5 and D6 is as follows 'lihe circuits through hands 21 and 21A and their respective Contact points' 53, are controlled by electric switch 56 (Figs. 1, 3 and 4) the operation of which is controlled by chronometer 38Athrough electro-magnets 54 and 55. Wheni chronometer hand 39 touches Contact point 44, electro-magnet 54 will be energized through line s which is connected to main "line A, thereby swinging switch'56 which carries armature 57, into engagement with Contact point 61. This completes the circuit from .mainline B through switch 56 and line n to hand 21". When chronometer hand 39 touches contact point 43, electro-magnet will be energized through line 7 which is connected t0 main line A, thereby swinging switch 56, which carries armature 57 into engagement with Contact point 62. This completes the circuit from main line B through switch 56 andline p to hand 21A. A spring pressed arm 60 (Figs. 3 and 4) yieldingly holds the switch 56 in either position.

As previously explained, when chronometer hand 39 touches contact 40, hand 21" on dial D5 is started.v At the same instant chronometer hand 39 engages contact 44 thus throwing switch 56 yon to contact 61 andl nascere closing the distance indicator operating cirlcuit through hand 21.l When chronometer lt will also be. seen that when either hand i 21 or 21A are reset to zero position, the contact points 53 will be inv an open circuit and therefore the passing of the hands backward over the contacts 53 will not aect magnet 63. Y

The distance indicator 69 has a resetting shatt 70l (Fig. 6) provided with a knurled headv 7,1, one revolution of which by hand resets all the numeral wheels' to zero in the usual way.

'lilo start the instrument, switch 72 (Fig. i

l) is opened. rlhis breaks all electrical con'.- nections.j Distance indicator 69 is manually reset to zero by one revolution of the reset'- ting head 71 (Fig. 6). rlihe revolution indicators are all reset to zero positionV by means of the hand operated pins 32 and 32A (Figs. 2,.5 and 7) as previously described. rlhe chronom'eter hand 39 (Fig. l) is set at starting point on contacts 40 and 44. Switch 72 is then closed. i'

By the closing of .switch 72 the instrument isv` started and all the lrevolution counters will start in unison, since chronometer hand 39 is on both contacts 40 and 44 and therefore energizes both magnets 37 and 37 A thus starting both the upper and lower sets. ot

revolution counters and throws switch 56.

onto contactl.u Pin 32A is then manually operated once thus shifting bar 31A once and the lower set of revolution counters will be stopped.y From now on the operation of the instrument will be entirely automatic, for

.when chronometer hand 39 reaches contact 45 the hands of the lower set of revolution counters will be reset. to zero, and when at the end of the first minute the hand 39 reaches contacts 41 and 43 the hands of the upper set of revolution counters Lwill be stopped simultaneously with the starting ot hands of the lower set and switch 56 will be thrown on to Contact 62; and so on as already eXplained'.

The expression ships instrument wherever it occurs throughout the specification and claims is used to denote an instrument of the character described whether employed on water craft or air craft, as the lprinciple of the invention is susceptible of adaptation ble balloons etc. driven by propelling means.

Also the term propeller as herein used denotes the ropelling .f means as a whole whether a single propeller ,or the average of a number'ofpropellers, unless limitedexpressly or by the contextto indicate a single` unit of multiple propelling means.

`ln so far as the instrument is'iised merely to register on the distance indicator the dis -i tance travelled, the graduations on dials D1. D2 etc-bf the revolution counters might be"v omitted, in which case the hands or pointers 2l, 21A, etc. merely become-'circuit closing members controlled-by the propeller speed for controlling the distance indicator circuits through contacts 53. 0r, circuit closing"J armsl or members otherv than the pointers 2l,

21A, etc. might be provided for engaging contactpoints arranged elsewhere thanon the dials, without departing from the principle of the invention It is also within the scope of the iiivent-ion to use spaced controlling elements other than electricalcontacts (53). f

The disks-D5, D6, carrying the contacts 53 may be made removable and interchangeable with other disks having differently spaced contacts calibrated according 'to .theI speed table of another ship, so that the same in- Vvstrument may be used for different ships by merely` changing the average speed dials.

Moreover provision `for interchanging the,

average speed dials on'the same shipinay be ofI impprtance V'It is well known that the distance-a ship will be driven by a certain i p* number of propeller revolutions per minute varies with external conditions of-the hull, load `or displacement, etc., more revolutions being required when the hull is foul, or when the vessel is loaded. A number of'average speed dials may be carried having Contact points calibrated according to varying conditions, and by 'using the appropriate dials the instrument will correctly register the distance travelled under various conditions.

From the foregoing it will be evident that the present invention is characterized by mechanism having .regular cycles ofopera- 'tion during predetermined recurrent intervals of time (each of the Contact members 21f'and` 21A completing their movements during successive minutesior other regular intervals) and, having means responsive to the speed of the propeller for regulating'the movement of the mechanism (the movement of contact members 21 and 21A being automatically' regulated both in rate and eXL tent), thereby to measure the travel whether at the `saine ordifferent speeds. Another yunique-characteristicof the invention is the intermittent character.- of said mechanism (the Contact members 21 and 21A stopping "i `and starting at predetermined intervals), the

intermittent mechanism preferably being os-v etc) the contacts may be moved 'relatively to the contact members.

It `,will also be evident-tliat the control means (rotary contacts. 21 distributed conl tacts 53, etc., in the illustratedlembodiment) are lso` constructed that the movement of the distance indicating means (69 in the illustration) varies during each' minute in accordance( with the variations in'ratio between propeller speed and distance traveled up to the current lspeed ofthe propeller. Eor example, if thel speed of the propeller' is 240 R. P. M., the distance indicator vaiies in speed during each minute rin accordance with` the Variationsy in spacing between the contacts 53 fromO upto 240 (see Fig. 9) and therefore in accordance witlrtlie variations' in ratio between propeller speed and distance traveled up to 240 R'. P. M., the curl rent speed. of `the;propeller.

Iclaim: l. A ships instrument 'comprising an. in-

dicato'r, and mechanism for successivelyadvancing said indicator including a stationary part and a movable part, one of the parts having contactsf distributed therealong re H traveled bya bodyr driven" by a propeller moving ina fluid medium, comprising con.- trolling Vmean's -movable vaccording .to the propeller motion duringv recurrentJ e inter- I vals, and indicating means movable inresponse to the controllingdneans, thefmove nient of the latter means varying t oughi out each intervalproportionately tog he variations in ratiofbetween propeller speedand distance traveled up to the. current speed oty the propeller. x i

3. A sliips instrumentcoinprising ya distance indicator, Nandjmeclianism controlled by the speed ofthe propeller during succes-g` sive predetermined periods -of` time' to measure on the distance indicator the distance the'ship has been driven.

.4. A ships instrument comprising a dis- Lregular cycles ofoperation during recurrent `predetermined periods of time and controlled byfthe speed-of the propeller automatically to measureonthe distance irdicator the distance the ship has b'eendriven ytance indicator, and mechanism having,

i mon to all pfthe propellers adapted auto-*- regular. cycles of movement during successive predetermined periods oit time, and means responsiveto the propeller speed to regulate the rate of movement of said mechai automatically and continuously to measure on the distance indicator the distance the ship has been driven whether at constant varying propeller speed.

l'. A ships instrument comprising a revolution counter, a distance indicator, mechanism controlled by the revolutions 4of the propeller to indicate on the revolution counterV the number oif revolutions ofv the propeller, and mechanism having regular cycles of operation during successive predetermined periods ot' time and controlled by then speed of the propeller through the revolution counter adapted automatically to measure on the distance indicator the distance the ship has, been driven whether at constant or varying propeller speed.

8. A ships instrument comprising a distance indicator, two ,revolution counters for each of a plurality of propellers, alternately actuatedfby the revolutions of the propeller associated therewith Vand mechanism commatically .and continuously tomeasure on the distance indicator the distance the ship has been driven Whether at constant or varying speed.

9. A ships instrument"comprising a distance indicator, two revolutions counters for each of a plurality of propellers, alternately actuated by the revolutions of the propeller associated therewith, two average revolution counters alternately actuated in proportion to the average of all the propellers, and mechanism controlled by the average revolution counters 'adapted automatically and continuously to measurev on the distance indicator the distance the ship has been driven whether at constant or varying speed.

10. A ships instrument comprising a distance indicator, two revolutions `counters alternately actuated by the revolutions Ot the propeller, and mechanism controlled by the speed of the propeller through the revolution counters adapted automatically and continuously to measure on the distance indicator the distance the ship has been driven whether at constant or varying speed.

1l. A ships instrument comprising a revolution counter, a distance indicator, mechanism controlled by the revolutions of the or4 means to place said electro-magnet alter- Lesser@ said indicator, said mechanism being ar-iranged automatically to drive said indicator at a rate proportional to the number of revolutions required to drive the ship a `predetermined distance at whatever speed the ship is being propelled.

12. A ships instrument comprisinga distance indicator, two controlling members therefor alternately actuated tor'predetermined periods ot' time in proportion to the number of the propeller revolutions.l electrical mechanism ,including an electro-magnet-for operating the distance indicator, and

nately under t-lie control of said controlling members during their respective periodsfof operation, whereby saidv distance indicator will be continuously operated. l

13. A ships instrument comprising a distance indicator,- two revolution counters alternately actuated for predetermined peri- 'ods of time in proportion to th-e number of the propellerrevolutions, electrical 'mechanism including an electro-magnet for operating the distance indicator, and means to placey said electro-magnet alternately under the control of said revolution counters during their respective periods of operation, whereby said distance indicator will be continuously operated' through said revolution counters.

14. A ships instrument comprising a distance indicator, a controlling -member theref for actuated in proportion to the number of 'the propeller revolutions, electrical mecha-y -tionately to the number ot revolutions oi? the propeller during a predetermined period of time, a series of stationar tcontrolling elements therefor, and a nova e controller actuated bythe revolution controlled mechanism moving synchronously with the propeller revolutions adapted to cooperate with said stationary controlling elements successively, to operate the distance indicator, said stationary controlling elements being spaced to correspond to the distance the ship' is driven during said predetermined period ot time at constant or varying speed.

, 16. A ships instrument comprising a disi tance indicator, mechanism controlled by the revolutions of the propeller to move proportionately to the number of revolutions of' the propeller during a predetermined period of time, electrical mechanism for operating' the distance indicator, a series of electrical contacts therefor, and a controlleractuatedbyf the revolution controlled mechanism moving, synchronously with the propeller' revolutions adapted to engagel said electrical contacts successively, to operate the distance indicator, said electrical ycontacts being spaced to correspond to the distance the ship is driven during said predetermined period of time atv constant or varying speedl v 17 A' ships instrument comprising a distance indicator, a revolution counter, mechanism controlled by the revolutions of the -propeller to actuate the revolution counter proportionately toY the numberiof revolutions of the propeller during a .predetermined p-eriod of time, mechanism for operating the distance indicator, a series of stationary controlling elements therefor', and a movable controller actuated by the revolution counter mechanism moving synchronously with thepropeller revolutions adapted to cooperate with said stationary controlling elements successiyely, to operate the distance indicator, said stationary controlling elements being spaced to correspond to the distance the ship is driven during said predetermined period of time at constant-or varying speed. l Y

18. A ships instrument comprising a distance indicator, a revolution counter, mechanism controlled by the revolutions of the propeller toactuate the revolution -counter proportionately to the number of revolutions of the propeller during ya 4.predetermined period of time, electrical mechanism for operating the distance indicator, a seriesof electrical contacts therefor, anda controller actuated by the revolution counter mechanism moving synchronously with the propeller revolutions adapted to engagesaid electrical contacts successively, to operate the distance indicator, saidelectrical contacts being spaced to correspond to the distance the ship is driven during said predetermined period of time' at constant or varying speed.

19. A ships instrument comprising a distance indicator, Vtwo controlling members therefor actuated alternately and proportionately to the number of revolutions of the propeller during predetermined periods of time, connections between said controlling members and said distance indicator to operate the latter, a chronometer, mechanism ccntrolled bythe chronometer toplace said controlling members alternately in operative relationship to the propeller, and mechanism controlled by the chronometerto place said connections betweenthe controlling members and the distance' indicator alternately in operative condition. Y

20. Apparatus for measuring the distance traveled by a body driven by a propeller moving in a Huid medium, comprising control members alternately movable according to the propeller motion, and indicating means movable in response to each movement ,of .the control members, eachy movement ofthe latter means varying throughoout its durationA in accordance with the' variations in ratio between propeller speed and distance traveled up to the current speed of the propeller. L

2l. y'A ships instrument comprising a distance indicator, two revolution counters' actuated alternately and-proportionately to the number` of revolutions ofthe propeller during predetermined periods of time, electrical connections between said revolution counters and said distance indicator to operate the latter, a chronometer, electrical mechanism controlled by thechronometer to place said revolution counters alternately in op- `'erative relationship to the propeller, and electrical mechanism controlled by the chronometer to place said connections between` the revolution counters and the distance indlcator alternately in operative condition.

22. A ships instrument comprising a distance indicatorfa revolution counter including a dial and hand, mechanism controlled by the ,revolutions of the propeller to actuate the hand proportionately to the number of revolutions of the propeller during apredetermined period of time, electrical mechanism for operating the distance indicator, .and aseries of electrical contacts on said dial adapted to be engaged successively by the hand, the'operating-circuit of said electrical mechanism including said hand and contacts, 'whereby the engagement of the hand With the contacts will operate the 'electrical mechanism which yoperates the distance indicator. .i

23. A ships instrument comprising a dis.-

tance indicator, mechanism controlled by the revolutions of the propeller tovmove proportionately to the number of revolutions of they propeller during a predetermined period of time, mechanism for operating the distance indicator including a removable member having a series of spaced controlling-elements adapted to be interchanged vwith other similar members having differently spaced controlling elements, and a movable controllerdactuated by the revolution controlled mechanism moving synchronously rwith the propeller revolutions adapted tov cooperate with said controlling elements successively, to operate the distance indicator.

24:. A ships instrument comprising a distance indicator, mechanism controlled .by the revolutions of the propeller to move proportionately 'to the number of revolutions of the vpropeller during a predetermined period of time, electrical mechanism Ifor operating the distance indicator including a removable member having a series of spaced' electrical contacts adapted to be interv changed With other similar members having determined period of time, electrical mechanism for operating the distance indicator, anda series ot electrical contacts on said dial adapted to be engaged successively by the hand, the operating circuit of saidv electrical mechanism including said hand and contacts, vvhereby the engagement of the hand With the contacts Will operate the electrical mechanism which operates the distance indicator, said dial being removable and adapted to be interchanged with other similar dials having diderently spaced series of -electrical contacts.

26. A ships instrument comprising speedcontrolled mechanism controlled by the revolutions of the propeller to move proportionately to the number of revolutions of the propeller during a predetermined period of time, tvvo movable members associated With and operated by said speed-controlled mechanism, automatic means 'for alternately connecting and disconnecting said movable members to and from said mechanism at predetermined intervals of time and a distance indicator alternately controlled' by said members.

27. A ships instrument comprising speedcontrolled mechanism controlled by the revolutions of the propeller to move proportionately to the number of revolutions of thepropeller during a predetermined period of time, two movable members associated with and operated by said speed-controlled mechanism, automatic means for alternately connecting and disconnecting said movable members to and from said speed-controlled mechanism, meansfor automatically resettin posgi'tion after being disconnected from said speed controlled mechanism and a distance indicator alternately controlled by said members.

said movable members to their initial' Leeaevo connecting and disconnecting said movable members to and from said speed-controlled mechanism, means for automatically res-etting said movable members to their initial position after being disconnected from said 7 mechanism, and means for-automatically operating said means at recurrent intervals and a distance indicator alternately controlled by said members.

30. A ships .instrument comprisin a distance indicator, mechanism intermittently movable throughout equal succeeding periods of time, and means controlled bylthe speed of the propeller to regulate the eX- tent of said movement, thereby to measure on the distance indicator the distance the ship has been driven Whether at the same or different speeds.

A31. ln a ships linstrument, travel indicating mechanism controlled by the ships propeller, said mechanism including means recurrently operative during equal periods of time irrespective of the rate of travel, an 'indicator controlled by said means, and means responsive to the speed of the propeller for automatically regulating the movement of said means during said periods to indicate the travel Whether at the same or different speeds.

32. In a ships instrument, travel indicating` mechanism controlled by the ships propeller, said mechanism .including oscillatory means moving in one direction during equal periods of time irrespective of the rate o travel, an indicator controlled by said means, and means responsive to the speed of the propeller for automatically regulating the movement of said means during 4said `periods to indicate the ytravel Whether at the same or different speeds.

33. A ships instrument comprising a dis-v4k tance indicator, and intermittent, mechanism having regular periods of operation throughout var lng speeds ofthe ship and controlled y the speed of the propeller automatically to measure on the distance indicator the distance the ship has been driven Whether at constant or varying propeller speeds.v

34. A ships instrument comprising a. distance indicator, mechanism intermittently movable throughout equal succeeding *pe-i riods ottime, and means controlled by the speed of the propeller to regulate the rate 4of` said movement, thereby to measure on the tance indicator, mechanism controlled by the revolutions of the propeller to move proportionately to the number of revolutions of the propeller during a predetermined period of time, a series of controlling elements and a controller adapted to cooperate. with the controlling elements successively, to'operate the distance indicator, said controlling elementsand said controller being movable relatively to each other in response to said first mechanism and said controlling elements being spaced to correspond to the distance the ship isy driven during said predetermined period of time at constant or varying speed.

37. A ships instrument comprising a/distance indicator, mechanism controlled by the revolutions of thepropeller to move proportionately to the number of revolutions of the propeller during a predetermined period of time, electrical mechanism for operating the distance' indicator, a series of electrical contacts therefor, and a controller adapted to engage said electrical contacts successively, to operate the distance indicator, said electrical contacts and said controller being relatively movable in proportion to the propeller revolutions and said electrical contacts being spaced to correspond to the distance the ship is driven during said predetermined period of time at constant or varying speed.

38. VA ships instrument comprising a distance indicator, a revolutionl counter, mechanism controlled by the revolutions of the propeller to actuate the revolution counter proportionately to the number of revolutions of the propeller during a predetermined period of time, mechanism foroperating the distance indicator, a series of controlling elements therefor and a `controller adapted to Vcooperate with the controlling elements successively, to operate the distance indicator, said controlling elements and controller being relatively movable in response to the revolution counter mechanism and said controlling elements being spaced to correspond to the distance the ship is driven during said predetermined period of time at constant or varyingspeed.

39. A ships instrument comprising a distance indicator, a revolution counter, mechanism' controlled by the revolutions of the propeller to actuate the revolution counter proportionately to the number of revolutions of the propeller during alpredetermined period of time, electrical mechanism for operating the distance indicator, a seiies of electrical contacts therefor, and a con-` troller adapted to engage said electrical contacts successively, to operate the distance indicator, said electrical contacts and controller beingrelatively movable synchronously with the propeller revolutions and said electrical -contacts being spaced to correspond to the distance the ship is driven during said predetermined period of time at constant or varying speed. y

'40. A ships instrument comprising a distance indicator, mechanism controlled by the revolutions of the propeller to move proportionately to the number of revolutions of the propeller duri-ng a predetermined period of time, mechanism for operating the distance indicatorv including a removable member having a series of spaced controlling elements adapted to be interclianged with other similar members having differently spaced controlling elements, and a controller' adapted to cooperate with said controlling elements successively to operate the distance' indicator, the controlling elements and controller being relatively movable synchronously With the propeller revolutions.

4l. A ships instrument comprising a distance indicator, mechanism controlled by the revolutions of the propellerto move proportionately tothe number of revolutions of the propeller during a predeterminedv period of time, electrical mechanism for operating the distance indicator including a removable member having a seriesof spaced electrical contacts adapted to be interc'hanged With other similar members having differently spaced electrical contacts, and a controller adapted to cooperate with saidl -controlling elements successively to operate .the distance indicator, the controlling elements and controller being relatively movable synchronously with the propeller revolutions.

42. A ships instrument comprising an indicator and mechanism for actuating said indicator including relatively movable electrical parts, one of t-he parts having electrical contact elements distributed in accordance with the relation between the speed of the propeller and the velocity of the ship throughout 4a lpredetermined range of propeller speeds, and means for producing relative movement between said parts in accordance with the propeller speed. 43. In a ships instrument an indicator, means including an elccti'omagnet for operating said indicator, a branched circuit lll leading to said electromagnet, means in each branch for intermittently closing the circuit to said clectromagnet, said means being controlled bythe speed of the ships propeller, and means fof rendering either of said circuit closing means operative.

44C. Apparatus for measuring the distance traveled by a body driven by a propeller' moving in a fluid medium, comprising con` trol means including rotary members advancing from the same initial positionY duringr alternate intervals of time, and common indicating'means continually advancing in response to alternate advances of said members, the control means being constructed to vary the movement of the indicating means throughout each interval in accordance With inesatte the variations in ratio between propeller 'speed and distance traveled up to the current speed of the propeller.

45. ln a ships instrument an indicator, means including an electromagnet for operating said indicator, the circuit leading to said electromagnet having tWo branches, means in each branch for intermittently closing the circuit to said electromagnet, said means being controlled by the speed of the shipls propeller, and means actuated at predetermined intervals for alternately rendering said circuit closing means inoperative.,

Signed by me at Boston, Massachusetts, this 18th day of August, 1919.

GEORGE WALKER. 

